Enter the first day of your last period, the average length of your cycle, and the current date into the calculator to determine your current menstrual cycle phase.
Cycle Phase Formula
The menstrual cycle is divided into four phases, and the phase is determined by the current day in the cycle:
- Menstrual Phase: Day 1 - Day 5
- Follicular Phase: Day 6 - Day 13
- Ovulatory Phase: Day 14 - Day 17
- Luteal Phase: Day 18 - End of Cycle
To determine the current cycle phase, calculate the number of days since the first day of the last period and then find the remainder when divided by the cycle length. This will give you the current day in the cycle, which can be used to determine the phase based on the ranges above.
What is a Menstrual Cycle?
The menstrual cycle is a series of natural changes in hormone production and the structures of the uterus and ovaries of the female reproductive system that make pregnancy possible. The cycle is required for the production of oocytes, and for the preparation of the uterus for pregnancy. The length of a menstrual cycle can vary, but the average is around 28 days.
How to Calculate Your Cycle Phase?
The following steps outline how to calculate your menstrual cycle phase.
- First, input the first day of your last period.
- Next, input the average length of your menstrual cycle in days.
- Then, input the current date.
- Click the "Calculate" button to find out the current phase of your menstrual cycle.
- The calculator will display the phase: Menstrual, Follicular, Ovulatory, or Luteal.
Example Problem :
Use the following variables as an example problem to test your knowledge.
First Day of Last Period = 03/01/2023
Average Cycle Length = 28 days
Current Date = 03/15/2023
